The present invention relates to lawn treatment carts used to spread or spray various known treatment materials which enhance lawn growth, destroy weeds, and the like.
Proper treatment and maintenance of a lawn must be periodically performed in order to ensure healthy lawn growth. As most homeowners are aware, lawn maintenance can be a long and tiring project. The specific type of maintenance required by a lawn will vary depending on such factors as the individual terrain characteristics, the climate, and the amount of previous care given to the lawn. However, proper lawn maintenance generally must include the application of various types of seed, fertilizers, insecticides, crabgrass control agents and other materials, depending on the condition of the lawn to be treated.
Prior to the invention of the spreader to be described herein, separate hand-operated apparatus for treatment of a lawn with either liquid or granular material were known. Treatment of a lawn with both liquid and granular material using these separate apparatus requires two distinct steps. The lawn is first treated with one type of material using one apparatus, and subsequently treated with the second material using another apparatus. The duplication of time, labor and costs using this procedure are evident.
Furthermore, although certain apparatus exist which are capable of both spreading granular material and spraying a liquid, these known apparatus are large vehicles similar to tractors or combines of the order of size of at least about 12 feet long. The granular spreading operation occurs at one end of the vehicle while the liquid spraying operation occurs at the other end. The relatively large separation of these two operations on the same vehicle was believed necessary to separate the spray from the granular spreading components to avoid "gumming up" of the granular spreading components, which would adversely affect such granular spreading operation. Moreover, the liquid pumping operation of such vehicles is coupled to the engine speed of the vehicle and not the distance travelled. Accordingly, uniform spraying of the liquid material on the treated terrain is not always possible.
The following U.S. Patents disclose various granular spreaders known to the art: U.S. Pat. Nos. 4,106,703; 3,544,013; 3,446,165; 3,438,585; 3,419,221; 3,220,369; 3,164,301; 2,946,597; 2,741,401; 2,661,955; 2,564,255; 2,550,872; 2,547,143; 2,120,169; 843,680; 841,982; 32,554. Norwegian Pat. No. 99,367 also discloses a granular spreader, and U.S. Pat. No. Des. 200,165 discloses a combine. Only granular material can be spread by the aforementioned spreaders.
U. S. Pat. No. 3,792,814 discloses an apparatus used to spray fertilizer. It includes a tank of liquid fertilizer pivotally mounted to a trailer which is adapted to be towed by a vehicle. This liquid sprayer is not capable of spreading granular material. Another separate step would be required to treat a lawn with granular material.
It is apparent from the aforementioned patents, which are typical of the lawn spreader art, that none of the disclosed compact or hand-operated spreaders or sprayers eliminates the duplication of work which must be performed by the operator of such compact apparatus. That is, since each of the disclosed carts performs only a single operation, an operator must first treat a lawn with either only a liquid or granular type material, and subsequently repeat the treatment with the other type material. This duplicative two-stage lawn treatment procedure is obviously time consuming and expensive.
Compact granular spreaders which are hand-operated by an operator, as for example the spreader disclosed in U. S. Pat. No. 4,106,703, include an endless rotatable spreader belt which receives granular treatment material and assists in dispersing the material on the lawn. In that patent, material deposited on the belt is fed into a rotating spinner plate for spreading on a lawn to be treated. Providing such a compact, hand-operated granular spreader with liquid spray capability would appear to be unfeasible because the size of the spreader is sufficiently small that mixing of the liquid spray with the granular spreader components is possible. Both the liquid in the spreader and the liquid mist sprayed from the spreader might moisten the granular spreader components causing them to "gum up", thereby adversely affecting the granular spreading operation. In any event, as evidenced by the aforementioned patents, there is no suggestion in the known compact, hand-operated lawn treatment art to provide a spreader capable of both spreading granular material and spraying liquid material. Also, as noted above, larger vehicles prevent mixing of liquid and granular materials by separating the two operations by a large distance. Obviously, this solution is impractical, if not impossible, in a small compact apparatus.
Thus, applying both granular and liquid material to a lawn requires either a two-step procedure using two different apparatus and duplication of effort, or use of a large and expensive vehicle to perform both operations.
The present invention provides a compact, hand-operated lawn treatment apparatus which enables its operator to selectively spread granular material, spray liquid material, or simultaneously spread and spray both types of material. The spreader is designed to prevent application of the liquid material on any of the granular spreading components. The duplication of steps now required to spread both granular and liquid material using a compact spreader, or the need to acquire a large and expensive vehicle to perform both operations, is eliminated by the present invention.
In a further aspect of the present invention, a known compact, hand-operated granular spreader can be readily retrofitted to provide a liquid spray capability.